Valve-gear for gas-engines.



Patented June 4, I90l.

No. 675,58l.

, a. ALUEBSON.

VALVE GEAR FDR GAS ENGINES.

(Application filed Jan. 25, 1901.)

2 Sheets-Sheet I.

(No 143ml.

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G. ALDERSON. VALVE GEAR FOR GAS ENGINES.

(Application filed Jan. 25, 1901.) (No Model.) 2 Sheets-Sheet 2 mumsPrrzas 0a.. morcyuwc" wmmm-on. a. c.

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GEORGE ALDERSON, OF LASALLE, ILLINOIS, ASSIGNOR TO CHARLES IERUNNER, OFPERU, ILLINOIS.

VALVE-GEAR FOR GAS ENOlNES.

SPEUIFIEJATIODT forming part of Letters Patent No. 675,581, dated June4., 1901. Application filed January 25, 1901. Serial No. 44,748. (Nomodel.)

To (tZZ whont it may concern:

Be it known that I, GEORGE ALDERSON, of Lasalle, Illinois, have inventedcertain new and useful Improvements in Valve-Gear for Gas-Engines, ofwhich the following is a speciiication.

My invention relates to improvements in valvegear for gas -engines of atype well adapted-for controlling the exhaust-valve of a gas or vaporengine in properly-timed relation to the other operating parts, althoughnot confined to this particular application.

More specifically, my invention relates to a valve-gear of thehit-and-miss type which controls the valve to interrupt the rechargingof the engine while the latter is running at an abnormal speed; and theinvention also contemplates a fine regulation and control of the speedof an explosive or internal-combustion engine through adelicately-adjustable spring controlled mechanism which determines theexact centrifugal effect of the governor-balls at which the valvemechanism will operate to hold open the exhaust-valve of the engine,thus causingthe omission of a power-stroke and the consequent slowingdown of the engine.

To these ends myinvention consists in the matters hereinafter set forth,and more particularly pointed out in the appended claims.

My invention is illustrated in the accompanying drawings, in whichFigure 1 is a central vertical section through the device embodying myinvention. Fig. 2 is a side elevation, partly in central verticalsection, of the device as viewed from the right in Fig. 1, the cam beingshown in another position; and Fig. 3 is a similar view as viewed fromthe left of Fig. 1.

In the drawings, 4 designates a block removably fastened to the side ofthe pillowblock of the engine above the driving-shaft in the latter.Fixed horizontallyin said block 4. is a stub-shaft 5, which carriesloose on its outer end the larger member 6 of the usual two-to-one gearcommonly employed to actuate the eXhaust-valve of four-cycle engines,said gear meshing with a smaller gear (not shown) fast on thedriving-shaft. On the inner face of gear 6 is formed or secured abevel-gear 7, which meshes with a smaller bevel-gear 8, fast on thelower end of the stem 9 of a centrifugal ball-governor 10, which stem 9is vertically journaled in an overhanging bracket 11, formed integralwith or secured on the block 4.

On an inwardly-extending hub 12 of the gear 6 is mounted a cam 13, whichcam may be secured in fixed relation to the gear 6, so as torotatetherewith on the shaft 5, by means of a threaded bolt 14., passingthrough said cam and the bevel-gear 7 and the web of the gear 6 andsecuring said parts rigidly together, as plainly shown in Fig. 1.

Straddling a loose collar 15 on the shaft 5 is the inner forked end of atappet 16, on the inner face of which is mounted a roller or otherantifriction projection 17. The outer end of the tappet is socketed, asat 18, to receive the inner end or shank of a valve-actuating rod 19,the latter being supported intermediate its length by a bracket 20 andbeing provided with a spring 21 for normally keeping the roller 17 onthe tappet pressed into engagement with the cam 13. The tappet 16 isprovided on its upper edge with a latchengaging member in the form of aprojection 22, and in the upper fork of the same is formed a socket 23,in which is seated a spring 24. At a convenient point on the block 4 ispivoted, as at 25, a latch 26, which latter is arranged to lie parallelwith and directly over the upper edge of the tappet 16 and is normallypressed upward by the engagement of the spring 2a with its lower side,as shown in Fig. 2. In the block at is also pivoted, at 27, a lever 28,the said lever being desirably disposed transversely to the latch 26 andhaving one arm thereof extending across and just above said latch,'asclearly shown in Figs. 1 and 2. The opposite arm of said lever 28 isadapted to receive a finely-regulable downward pressure by means of aspring 29, housed in a vertical recess 30, formed through the upper partof the block 4., the upper end of said spring contacting the lowerheaded end of a thumb screw 31, screwing vertically through a cap 32,which closes the upper end of recess 30. The inwardly-extending arm oflever 28 abuts the lower end of a vertical rod 83, which latter ismounted in and coaxially with the stem 9 of the governor 10, so as to becapable of an endwise-sliding movement therein. The upper end of rod 33has ahead 34, adapted to be engaged by the inner ends of the ball-leversof the governor, as plainly shown in Fig. 1.

35 represents a washer fixed on the shaft 5, interposed between thecollar 15 and the end of the shaft-bearing.

The operation of the device is as follows: In the normal operation ofthe engine the tappet 16 and its connected valve-actuating rod 19 arereciprocated by the cam 13 and the spring 21 at the proper time andduring the proper interval to force and hold open the exhaust-valve ofthe engine. During such operation the point of latch 26 is held up andout of engagement with the projection 22 on the tappet by the engagementof the spring 24 with the under face of said latch. Whenever, however,the speed of the engine exceeds the normal, the spreading of thegovernor-balls through the rod 33 and the lever 28 depresses the latch26 against the action of spring 24, its point dropping into engagementwith the projection 22, whereby the re ciprocating tappet 16 is heldlocked in its outermost position against the thrust of the returningspring 21, and the exhaust-valve of the engine is thereby maintainedopen. This interrupts the drawing in of the explosive charge and causesthe engine to run by its own momentum, during which period it pumps airidly back and forth through the open exhaust-valve, whereby the speed ischecked and decreased until the falling of the governor-balls againpermits the latch 26 to be raised out of engagement with the projection22, whereupon the valve-actuating rod 19 is again reciprocated regularlyand the engine resumes its normal operation. By the provision of thespring-tensioned lever 28 intel-posed between the governor-controlledrod 33 and the latch 26 a finely-adjustable resistance is interposed tothe positive action of the governor, which has to be overcome by thegovernor before the latter becomes effective to depress the latch 26.The degree of this resistance is determined by the compression to whichspring 29 is subjected by the thumb-screw 31 in an obvious manner. Bythis means the exact maxiiri'um speed at which the engine will bepermitted to run at any given operation or under any given load or underany given fuel conditions may be accurately regulated and determined bythe simple operation of turning a thumb-screw.

My invention is not limited to the precise details of construction andarrangement hereinabove described, and shown in the drawings. Forinstance, it is plain that other and mechanically-equivalent means forsecuring the cooperative action between the latch and the tappet mightbe employed. Other and mechanically-equivalent means for applying thefinely-tensioned resistance to the positive action of the governor wouldalso suggest themselves to one skilled in this art in the light ofcv'spel what I have herein shown and described. I wish it to beunderstood that such modifications and equivalents would be fully withinthe spirit and intended scope of my invention.

I claim as my invention- 1. In a valve-gear for gas-engines, thecombination with the exhaust-valve and a valveactuating rod of a tappetin which the shank of said rod is held, a cam for imparting an outwardmovement to said tappet and rod to open the exhaust-valve atproperly-timed in"- tervals, a spring for imparting the return movementto said tappet and rod, a latch pivoted adjacent said tappet, alatch-engaging member on said tappet, a spring on said tappet normallyholding said latch out of engagement with said latch-engaging member,and a governor operating to force said latch into locking engagementwith said latch-engaging member, and thereby hold open the exhaust-valvewhen the speed of the engine becomes excessive,substantially asdescribed.

2. In a valve-gear for gas-engines, the combination with theexhaust-valve and mechan= ism for opening the same at the proper intervals and a governor, of a locking device adapted to be forced by thegovernor into locking relation to said exhaust-valve mechanism so as tohold said valve open when the speed becomes excessive, a lever havingone arm interposed between said governor and said locking device, aspring acting on the other arm of said lever in a direction to opposethe centrifugal effect of the governor, and means for regulating thetension of said spring, substantially as described.

3. In a valve-gear for gas-engines, the combination with theengine-frame and the exhaust-valve, of a stub-shaft fixed therein, aforked tappet, the inner forked end of which straddles said stub-shaftand the outer end of which is adapted to receive a valve-actuating rod,said tappet being further provided with a projection on its upper edge,a cam on said stub-shaft for actuating the tappet, means for actuatingsaid cam from the'driving-shaft of the engine, a latch pivoted to theengineframe, the free end of which is adapted to engage said projection,a spring seated in a recess in the upper edge of the tappet and normally tending to press said latch out of engagement with saidprojection, and a centrifugal governor journaled in the engine-frame,the endwise-movable rod of which operates to force said latch intolocking engagement with said projection when the speed becomes excessive,substantially as described 41-. In a valve-gear for gas-engines, thecombination with the engine-frame and the exhaust-valve, of a stub-shaftfixed therein, a forked tappet, the inner forked end of which straddlessaid stub-shaft and the outer end of which is adapted to receive avalve-actuating rod, said tappet being further provided with aprojection on its upper edge, a cam on said stub-shaft for actuating thetappet, means IIO for actuating said cam from the driving-shaft of theengine, a latch pivoted to the engineframe, the free end of which isadapted to engage said projection, a spring seated in a recess in theupper edge of the tappet and normally tending to press said latch out ofengagement with said projection, a centrifugal governor journaled in theengine-frame, the endWise-movable rod of which operates to force saidlatch into locking engagement with said projection when the speedbecomes excessiv'e, a lever pivoted in the frame and having one arminterposed between the governorstem and the latch, a spring acting onthe other arm of said lever in a direction to oppose the centrifugaleffect of the governor and means for regulating the tension of saidspring, substantially as described.

GEORGE ALDERSON.

Witnesses:

HENRY REAM, JosEPH J. LINNIG.

